Search results for "startle"
showing 9 items of 29 documents
Hyperekplexia caused by dominant-negative suppression of glyra1 function.
2007
Hyperekplexia (HE; startle disease; OMIM#149400) is a rare inheritable neurologic disorder characterized by an exaggerated response to sudden stimuli, muscular rigidity, and hyperreflexia, leading to chronic injuries due to unprotected falls. All symptoms are present at birth but gradually decline during the first year of life, although an exaggerated startle response remains during adulthood.1 Dysfunctional inhibitory neurotransmission by glycine (Gly) plays a central role in HE pathogenesis. All patients with HE carry mutations in genes encoding either for α1 (GLYRA1) or β (GLYRB) Gly receptor subunits, presynaptic Gly transporters (SLC6A5), or proteins involved in Gly receptor (GLYR) clu…
Chapter 9 The effects of a prepulse on the StartReact phenomenon
2006
Publisher Summary This chapter presents a study to investigate whether the inhibitory effects of the prepulse are different in the condition of motor preparation with respect to that of unexpectancy and whether the inhibition of the startle reaction by a prepulse is associated with the inhibition of the StartReact phenomenon. The chapter demonstrates that the procedure could help in ascertaining whether reflex and volitional components are actually combined in the StartReact phenomenon. Eight healthy volunteers, six men and two women, aged between 25 and 52 years were investigated and the startle reaction was recorded with surface electrodes over the right orbicularis oculi muscle and, in t…
A novel arousal-based individual screening reveals susceptibility and resilience to PTSD-like phenotypes in mice
2021
Translational animal models for studying post-traumatic stress disorder (PTSD) are valuable for elucidating the poorly understood neurobiology of this neuropsychiatric disorder. These models should encompass crucial features, including persistence of PTSD-like phenotypes triggered after exposure to a single traumatic event, trauma susceptibility/resilience and predictive validity. Here we propose a novel arousal-based individual screening (AIS) model that recapitulates all these features. The AIS model was designed by coupling the traumatization (24 h restraint) of C57BL/6 J mice with a novel individual screening. This screening consists of z-normalization of post-trauma changes in startle …
Prepulse inhibition can predict the motivational effects of cocaine in female mice exposed to maternal separation
2020
The prepulse inhibition (PPI) of the startle response can identify the rodents that are more sensitive to the effects of cocaine. Mice with a lower PPI presented a higher vulnerability to the effects of cocaine and a higher susceptibility to developing a substance use disorder (SUD). Maternal separation with early weaning (MSEW) is a relevant animal model to induce motivational alterations throughout life. Nevertheless, only a few studies on females exist, even though they are more vulnerable to stress- and cocaine-related problems. Hence, the aim of the present study was to evaluate the ability of PPI to identify females with a greater vulnerability to the long-term consequences of early s…
Increasing intensity of deimatic behaviour in response to repeated simulated attacks: a case study on the mountain katydid (Acripeza reticulata)
2022
Abstract How and when deimatic behaviours are performed can change during encounters between predators and prey. Some predators attack repeatedly, investigating and manipulating prey, and in response, an individual’s deimatic behaviour may intensify or may diminish in favour of escaping. The presence of a resource can further force a trade-off between displaying and escaping. Here, we examined the intensity of the katydid’s deimatic behaviour, a visual display, the propensity of their escape response under repeated simulated attacks, and how these responses change in the presence of foraging resources. We found that display intensity increased with repeated simulated attacks and that femal…
A synthesis of deimatic behaviour
2022
Deimatic behaviours, also referred to as startle behaviours, are used against predators and rivals. Although many are spectacular, their proximate and ultimate causes remain unclear. In this review we aim to synthesise what is known about deimatic behaviour and identify knowledge gaps. We propose a working hypothesis for deimatic behaviour, and discuss the available evidence for the evolution, ontogeny, causation, and survival value of deimatic behaviour using Tinbergen's Four Questions as a framework. Our overarching aim is to direct future research by suggesting ways to address the most pressing questions in this field. peerReviewed
Rats with elevated genetic risk for metabolic syndrome exhibit cognitive deficiencies when young
2021
Metabolic syndrome (MetS) is a known risk factor for cognitive decline. Using polygenic rat models selectively bred for high and low intrinsic exercise capacity and simultaneously modelling as low and high innate risk factor for MetS respectively, we have previously shown that adult animals with lower exercise capacity/higher MetS risk perform poorly in tasks requiring flexible cognition. However, it is not known whether these deficits in cognition are present already at young age. Also, it is unclear whether the high risk genome is related also to lower-level cognition, such as sensory gating measured as prepulse inhibition. In this study, young and adult (5-8 weeks and ∼9 months) rats sel…
Prenatal exposure to diazepam and alprazolam, but not to zolpidem, affects behavioural stress reactivity in handling-naïve and handling-habituated ad…
2002
A gentle long-lasting handling produces persistent neurochemical and behavioural changes and attenuates the impairment in the behavioural reactivity to novelty induced by the prenatal exposure to diazepam (DZ) in adult male rat progeny. This study investigated the consequences of a late prenatal treatment with three GABA/BDZ R agonists (DZ) alprazolam (ALP) and zolpidem (ZOLP)), on different stress-related behavioural patterns, in non-handled (NH), short-lasting handled (SLH) and long-lasting handled (LLH) adult male rats exposed to forced swim test (FST), acoustic startle reflex (ASR) and Vogel test (VT). The effects on motor activity were evaluated in the open field and in the Skinner box…
Ikääntymisen ja synnynnäisen aerobisen suorituskyvyn vaikutukset varhaiseen tiedonkäsittelyyn rotilla
2016
Fyysisen aktiivisuuden vaikutukset aivojen toimintaan ja kognitiivisiin kykyihin ovat viime aikoina herättäneet kiinnostusta tutkijoiden keskuudessa. Näitä teemoja tutkii myös Active, Fit and Smart (AFIS) -tutkimushanke, jonka päämääränä on selvittää liikunnan yhteyksiä oppimiseen ja sen edellytyksiin elämän eri vaiheissa. Tämä tutkielma on toteutettu osana AFIS-projektia, ja se lähestyy aihetta aerobisen suorituskyvyn näkökulmasta. Tutkielman tavoitteena on selvittää, miten synnynnäinen aerobinen suorituskyky ja ikääntyminen vaikuttavat varhaiseen tiedonkäsittelyyn, joka sijoittuu aivan kognitiivisen tiedonkäsittelyketjun alkuun. Tämä tapahtui vertailemalla kahta synnynnäiseltä aerobiselta…